package com.itheima2;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;

public class Work1 {
    public static void main(String[] args) {

        Collection<String> c = new ArrayList<>();

        c.add("ArrayList");
        c.add("LinkedList");
        c.add("HashSet");
        c.add("TreeSet");
        c.add("HashMap");
        c.add("TreeMap ");
       /* Iterator<String> it = c.iterator();
        while (it.hasNext()){
            System.out.println(it.next());
        }*/
        System.out.println(c);
    }
    }

